Vetsulin
Vetsulin, manufactured by Intervet and known in some countries as Caninsulin, is a veterinary porcine lente Intermediate-acting insulin, made up of 30% semilente (short-acting) and 70% ultralente (long acting) insulins. Vetsulin is FDA-approved for use in dogs and cats, under the trade name Vetsulin. However it was often used in the US legally "off label" for cats, prior to formal approval. How it works in dogs The majority of dogs on Caninsulin/Vetsulin (two-thirds) also will require twice-daily injections. Intervet says that many dogs stabilize better on twice-daily insulin injections. They also point out that when shots are given twice instead of once daily, there are less hypoglycemia incidents and better blood glucose control. Most vets are also not in favor of once-daily use because it is harder to regulate a dog on once-daily insulin than twice-daily dosing. Caninsulin/Vetsulin is a lente insulin, which is classed as intermediate, not long acting. Long acting insulins (such as Lantus, Ultralente, PZI) have a poor success rate among dogs. Canine activity graphs Pharmacokinetics graph of Vetsulin . Two peaks are depicted, one for the fast acting semilente insulin, and one for the slow acting Ultralente insulin. However, all dogs do not show two peaks of insulin activity. Once-daily vs twice-daily injections This blood glucose graph of Somogyi rebound shows a dog on once-daily porcine lente injections. You can see how the large insulin dose in once-daily regimens produces a steep low at insulin peak. Note: values are shown in mmol/l (non-US) measurement. Contrast this with a blood glucose graph with a twice-daily insulin regimen where food and insulin are given on a 12 hour basis. Note: values are shown in mmol/l (non-US) measurement. Further Information It is a veterinary use prescribed insulin and in most countries must either be purchased directly from your vet or with a prescription. In Canada, Caninsulin is available OTC, or over the counter online. It is also available online with a prescription in some countries, and may cost less that way. Caninsulin and Vetsulin can be purchased in three ways: a pack of ten 2.5ml vials, the more traditional 10 ml vial or a single vial of 2.5ml. Cats and and small dogs can get new vials monthly without wasting. VetPen MSD Animal Health has recently brought a refillable Caninsulin pen onto the market. Previously, no pens were designed for use with Lente-type insulins as the glass ball used to resuspend the insulin shattered the large Ultralente crystals present in both Ultralente and Lente insulins. The VetPen is designed to allow resuspension of the insulin without this occurrence. There are two sizes of VetPens. One (tan cap) dispenses insulin doses from 1 to 16 units (IU) per dose in full unit increments. The other (blue cap) dispenses 0.5 (1/2) to 8 unit doses in full or half unit increments. Both pens use 2.7 ml insulin cartridges which hold a total of 108 units (IU) of U40 Caninsulin. The pen uses pen needles that are 29 gauge and 1/2" (12.7 mm) long. The pens are operated and maintained like those designed for human use. As with other insulin pens, the pen and its in-use cartridge do not need to be refrigerated. Caninsulin/Vetsulin syringes Because Vetsulin is a U40 insulin, U40 syringes are the most helpful. If you choose to use a U100 syringe, you must do the U40 to U100 conversion. The conversion is not difficult and can give you precision of 0.2 units for those animals needing a more precise dose. Caninsulin/Vetsulin branded syringes do not appear the same world-wide. Technical details Vetsulin is a pork-based lente insulin. It is a suspension of crystalline (ultralente) and amorphous (semilente) insulins in a 70/30 ratio, as are all Lente insulins. Iletin II Lente by Eli Lilly and Monotard Pork by Novo Nordisk were pork lente insulins, as is Betasint Porcine Lente U80 and U100. The difference between them is: Vetsulin/Caninsulin is made by Intervet for veterinary use and is a U40 strength insulin--the Lilly and Novo insulins were U100 strength. U40 insulin is more convenient for small animals since it's more dilute and you can therefore give fine doses more easily. Lente CHO is a U80 insulin. Vetsulin is an aqueous suspension of insulin containing 40 IU per ml of highly purified porcine insulin (Lente); 30% is amorphous (non-crystallized) zinc (Semilente) insulin and 70% crystalline (in crystal form) zinc (Ultralente) insulin. The difference between Vetsulin and both Iletin II Lente made by Eli Lilly and Monotard Pork made by Novo Nordisk is this: Caninsulin/Vetsulin is a veterinary insulin of U40 strength. Both Novo's and Lilly's insulins were U100 strength. Beta Laboratorios of Argentina offers Betasint Porcine Lente in U 40, U80 and U 100 strengths while Polfa Tarchomin of Poland offers Lente CHO in U80 strength. Vetsulin contains porcine insulin. Porcine insulin is identical to canine insulin, but differs from human insulin in respect of one key amino acid. Porcine insulin differs from feline insulin in 3 amino acid positions shown in the table below. Human insulins (i.e. Lantus) differ from from feline insulin by all four key amino acids. Why Lente doesn't equal 70/30 Let's look at the differences in the two insulins. Lente is comprised of 70 % long-acting Ultralente insulin and 30% short-acting Semilente insulin. So proportions of a long-acting and short-acting insulin are being combined to produce a intermediate-acting insulin. Both Ultralente and Semilente insulin are suspended by adding zinc and the size of their respective insulin crystals. The largest insulin crystals are those of Ultralente, while Semilente contains the smallest, or microcrystals. Simply put, you're combining a long insulin and a short insulin to make an intermediate-acting one. 70/30 insulin starts with 70% NPH/isophane insulin, an intermediate-acting insulin which is suspended by protamine. To that, 30% R/neutral/normal insulin, which is short-acting and soluble, meaning there is no suspension; nothing is added to this insulin to delay its action. In this case, you are taking an intermediate-acting insulin with a suspension and adding to it a short-acting one with no suspension to create an intermediate-acting insulin. So we have an insulin (Lente), made up of a long-acting and short-acting insulin, both with zinc suspensions, and a mixed insulin (70/30), made from an intermediate-acting protamine suspended insulin and a short-acting one without any suspension. Because of these differences, the insulin action profile for these two insulins is going to be quite different, even though both insulins are classed as intermediate-acting. What Lente Is Not No Lente-type insulin regardless of species can contain any NPH/isophane insulin or any R/Neutral insulin. Both are chemically impossible: the phenol preservative present in NPH/isophane alters the action of Lente-type insulins, creating a mixture with an approximate action of R/Neutral. The zinc suspension of Lente-type insulin binds R/Neutral, causing the short-acting insulin to slow, losing its short-acting effect. Note--in 1980, there were no r-DNA/GE/GM insulins Previously,Lente-type insulins could not be dispensed in pen or cartridge form because the glass ball used formerly to mix the insulin in these devices shattered the Lente crystals. Combining Lente Family Insulins Insulin manufacturers indicate that R/neutral and semilente, Lente, ultralente insulins are able to be combined in the same syringe, but only just before injection. In pre-filled syringes, the zinc suspension of the Lente-type insulins binds the R/neutral, causing it to lose its short-acting effect. Various studies have documented this, and some doctors advise against using R/neutral in the same syringe with the Lente family of insulins. The following are lente type zinc suspension insulins but since they are produced for use in animals, they are not found in BNF, but in its sister veterinary formulary. These fall into the category of intermediate-length insulins. References More Information *Efficacy & Safety of a Purified Porcine Insulin Zinc Suspension for Managing Diabetes Mellitus in Dogs David Laxton, et. al., 2005, Journal of the American Veterinary Medical Association. *Evaluation of an insulin zinc suspension for control of naturally occurring diabetes mellitus in dogs Horn, B., Mitten, RW., 2000, Australian Veterinary Journal Citing David B. Church's study equating Caninsulin with Monotard Pork, thus the need for two shots a day in dogs. *Correspondence:Evaluation of an insulin zinc suspension for control of naturally occurring diabetes mellitus in dogs-page 2 Horn, B., Mitten, RW. 2001, Australian Veterinary Journal Drs. Horn & Mitten Respond to Caninsulin Once-Daily Dosing Claims for Dogs. * Caninsulin web site * Vetsulin web site *Use in rabbits Though not licensed/approved for use in rabbits, Intervet presents some helpful information on using Caninsulin/Vetsulin for them. *Intervet UK-Caninsulin Product Data Sheet *Endocrinology Symposium 2006-Selecting an Insulin for Treatment of Diabetes Mellitus in Dogs & Cats-page 39 Nelson, Richard, 2006, -OSU Endocrinology Symposium *Better Medicine-E-Newsletter-June 2006 Intervet *NACDS-Insulin Chart-Page 2 *Insulin therapy for dogs and cats Dowling, Patricia, September 1995, Canadian Veterinary Journal A discussion of Iletin insulins. *Lente Insulins-Injectable Suspensions West Virginia University College of Pharmacy-2009 Category:Pork Lente Category:Insulins Category:porcine Category:Lente Category:intermediate-acting Category:Zinc Category:Intravenous use NO Category:Methylparaben Category:Acetate Category:Currently marketed insulins Category:Rx Status Category:Content Category:Veterinary